Skylab, a science and engineering laboratory, was launched into Earth orbit by a Saturn V rocket on 14 May 1973. Three crews of 3 men each visited the station, with their missions lasting 28, 59, and 84 days.

Circling 50 degrees north and south of the equator at an altitude of 435 km, Skylab had an orbital period of 93 minutes. There were a plethora of UV astronomy experiments done during the Skylab lifetime, as well as detailed X-ray studies of the Sun.